The idea of an oven with adjustable cooking chambers is known, and in particular, separate consumer cooking ovens with adjustable heating elements and heating space dividers are known. Several efforts have been made to provide a smaller cooking space for baking ovens. Such ovens are frequently used in pizzerias, bakeries, fast food restaurants, groceries, and the like, in which standardized cooking spaces are desirable for commercial production to reduce cost, maximize use of space, and more evenly heat the interior. Flexible ovens for the use in homes, which can be transformed from larger to smaller spaces, have been a challenge for designers.
U.S. Pat. No. 5,994,673 ('673) teaches a variable volume oven that allows the volume to be adjusted according to the cooking load by providing a heating element that is vertically adjustable within the oven to a position that provides better convective and radiative heating to the cooking load. Supporting grooves are provided along the sides to support the heating elements at each level in which an exposed electric plug (to accommodate the heating element) is located. The oven floor is not adjustable in the '673 patent, and a smaller cooking space is not provided for; however, the heating element is closer to the cooking foods, but still heats the area beneath the cooking element.
U.S. Pat. Nos. 7,442,901 and 7,183,520 each disclose electric ovens which have heating space dividers with separate convection heating systems that are separately operable. The heating space dividers fit along groves or supports analogous to rack supports. Similarly, U.S. Pat. No. 7,071,448 teaches a cooking chamber with a partition member for a conventional electric oven, except that two vents are provided, and electrical cooking elements are provided at the top and bottom of the larger oven chamber; the partition member simply being insertable into grooves along the sides of the chamber. These inventions lack truly adjustable oven bottoms, and merely describe solid partitions for use to separate ovens into two separate cooking areas. Furthermore, none of these references describe oven doors that accommodate the adjustable oven parts, but are instead conventional oven doors.
Examples of related patents include an old U.S. Pat. No. 2,218,961 from 1939 that describes a gas range construction which has an adjustable broiler and broiler pan that may be moved up and down the inside of the oven to form a smaller cooking chamber. Another arcane patent includes U.S. Pat. No. 1,586,738 which teaches a cooking apparatus with an adjustable heating chamber. U.S. Pat. No. 5,928,544 shows a cooking applicant with movable base unit having two heating elements providing heat from above or below the food cooked. U.S. Pat. No. 2,498,554 teaches a detachable bottom for ovens or broilers. The British patent GB 430,103 teaches improvements relating to cooking ovens having partitions disposed therein through grooves disposed along the sides of the heating chamber.